1. Field of the Invention
The present invention relates to an apparatus and method for preventing condensation in machines processing web-like material. More particularly, the present invention relates to an apparatus and method for preventing condensation in a printing press by controlling temperatures in an area of a printing unit of a printing press.
2. Description of the Related Art
In print shops and press testing facilities there has been a problem that on high-speed machines, condensation occurs on those safety elements, such as finger guards, vital to protecting the press operating staff as well as on other sub-systems of the printing press. Condensation on a guard can be, for example, in the form of droplets on the surfaces which can collect to form drops dripping either onto the surface of the web-type material to be printed upon or into the printing unit itself, thereby causing print defects and other undesirable conditions. Condensation below the web-type material can cause print defects as well, for example, when droplets drip onto surfaces of vibrator rollers or the like of a lower printing unit.
Even on other printing unit components such as shields, rails, frame parts or tail tuckers, condensation may also occur in the form of droplets dripping on the web or on components of the ink train, thus posing a risk for maintaining print quality. For example, condensation of water on the surface of print unit rolls, especially the rolls in the dampening system of a printing press, can have a detrimental effect on the water feed in the lithographic printing process--condensed water added to the dampening solution on a roll can exceed the capacity of the nip resulting in excess water build-up and excess water in the nip can result in unstable water feed, thereby reducing print quality. Indeed, drips onto the web can cause direct lithographic errors and condensation on a roll, especially dampener rolls, can destabilize the lithographic process.
It is an object of the present invention to prevent defects on printed material from a printing press due to condensation. It is another object of the present invention to maintain the air temperature surrounding a selected area of a printing press to prevent condensation.